Compact copying machine with multiple-function reciprocating carriage

ABSTRACT

A copying machine of the Electrofax type having a stationary horizontal transparent support for receiving manuscript to be copied and a carriage mounted for horizontal movement beneath the transparency to effect optical scanning of the manuscript. The carriage supports means for feeding copy paper vertically past an image-receiving zone, a mirror which projects an image from the manuscript horizontally toward the image-receiving zone, lens means between the mirror and the image-receiving zone for focusing the image on the surface of the copy paper, a toner receptacle and means for feeding the copy paper therethrough after exposure thereof. Means are provided for moving the carriage horizontally in exact synchronism with vertical movements of the copy paper whereby a panoramic image from the manuscript is applied to the copy paper. The carriage-moving means includes a pulley mounted upon and rotated jointly with a paper feed roll and a traction cable wrapped about the pulley and adapted to be connected to opposite ends of the machine. Means are provided for tightening the cable whereby rotation of the pulley causes the pulley to rotate along the cable and thus move the carriage in synchronism with the paper feed roller.

United States Patent Hunt et al.

[72] Inventors: Robert A. Hunt, Silver Creek; Joseph M.

Rait, Buffalo, both of NY.

[73] Assignee: Pelorex Corp., Buffalo, NY.

[22] Filed: July 19, 1968 [21] Appl. No.: 746,127

[52] U.S. Cl.. ..355/8, 355/10 [5 l] Int. Cl. ..G03g 15/22 [58] Field ofSearch ..355/8, 52, 64, 65

[56] References Cited UNITED STATES PATENTS 1,966,261 7/1934 Petit et al..95/15 3,45l,752 6/1969 Frank ..355/8 3,421,816 1/1969 Robertson et al..355/8 Primary ExaminerSamuel S. Matthews Assistant Examiner- KennethC. Hutchison Attorney-Christel & Bean [5 7] ABSTRACT A copying machineof the Electrofax type having a stationary horizontal transparentsupport for receiving manuscript to be copied and a carriage mounted forhorizontal movement beneath the transparency to effect optical scanningof the manuscript. The carriage supports means for feeding copy papervertically past an image-receiving zone, a mirror which projects animage from the manuscript horizontally toward the image-receiving zone,lens means between the mirror and the image-receiving zone for focusingthe image on the surface of the copy paper, a toner receptacle and meansfor feeding the copy paper therethrough after exposure thereof. Meansare provided for moving the carriage horizontally in exact synchronismwith vertical movements of the copy paper whereby a panoramic image fromthe manuscript is applied to the copy paper. The carriage-moving meansincludes a pulley mounted upon and rotated jointly with a paper feedroll and a traction cable wrapped about the pulley and adapted to beconnected to opposite ends of the machine. Means are provided fortightening the cable whereby rotation of the pulley causes the pulley torotate along the cable and thus move the carriage in synchronism withthe paper feed roller.

8 Claims, 6 Drawing Figures PAIENTED JANZS I972 SHEET 10F 3' INVENTORSROBERT A. HUNT a By JOSEPH M. RAIT M? @W A TTOPNEYS PATENTED JAN25I972SHEET 2 BF 3 IN V EN TORS ROBERTA. HUNT &

JOSEPH M. an r ATTORNEYS PATENTED ms m2 SHEEI 3 BF 3 A TTORNEYJ'BACKGROUND OF THE INVENTION This invention relates to the reproductionof documents and the like by electrophotography and, more particularly,by processes of the type wherein the copy paper is renderedphotosensitive by applying an electrostatic charge to the surface of thecopy paper.

In .certain types of electrostatic copying processes and apparatus themanuscript to be copied is held in a stationary position and the surfacethereof is exposed to optical scanning means which projects an image ofthe manuscript to an electrostatically sensitized copy sheet. In suchapparatus the copy SUMMARY OF THE INVENTION The present inventionprovides a relatively simple and compact copying machine wherein themanuscript to be copied is supported face down upon a transparentsurface at the top of the apparatus and a carriage passes beneath thesame to scan the material of the manuscript. Virtually all of theoperating instrumentalities of the copying machine are mounted upon thiscarriage, that is, a mirror for projecting a scanned image from themanuscript, as the carriage moves in a plane parallel to the surface ofthe manuscript, lens means for directing this image horizontally to asheet of sensitized copy paper, means for electrostatically sensitizingthe sheet of copy paper, and

means for moving the sensitized copy sheet vertically past the projectedfield of the optical means at a speed exactly synchronized with thehorizontal movement of the carriage.

Speaking generally, the principal power-driven feed roll of the paperfeed mechanism is driven by electric motor means and the arrangement forpropelling the carriage along beneath the manuscript is driven directlyfrom this powered paper feed roll. A pulley connected directly to thepowered paper feed roll for rotation therewith has a cable wrappedaround the same and the ends of the cable are anchored to opposite endsof the machine. Accordingly, rotation of the paper feed roll and thepulley fixed thereto causes the pulley in effect to roll along thecable. The effective diameter of the pulley and the effective diameterof the paper feed roll are the same. By this means paper feed movementsresulting from the copy paper being pulled past the image zone of thelens means by the powered paper feed roll are exactly duplicated bymovements of the pulley along the cable which produce horizontalmovements of the carriage.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a longitudinalcross-sectional view through one form of the apparatus of the presentinvention;

FIG. 2 is a somewhat schematic skeletonized perspective view of thedrive and transmission means of the apparatus of FIG. 1;

FIG. 3 is a general top plan view of the apparatus of FIG. 1;

FIG. 4 is a fragmentary cross-sectional view taken on the line.44 ofFIG. 1;

FIG. 5 is a view similar to FIG. 4 but showing fragmentarily the controlshaft biasing means of FIG. 4 and taken on the line 5-5 of FIG. 1; and

FIG. 6 is a fragmentary view similar to FIG. 1 but showing apparatus forapplying a dry powdered toner to. the exposed copy paper instead'of theliquid toner contemplated in the apparatus of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first particularly toFIGS. I and 3, the general framework of the machine compriseslongitudinal sidewalls l0 and II which are held in fixed spacedrelationship by upper and lower end members designated 12 through 15 inFIG. 1; A

transparent panel 16 of glass or clear plastic extends across the frameof the machine at the top thereof as shown in FIG. I and the manuscriptto be copied is placed face down upon the panel 16.

A carriage assembly is designated generally by the reference numeral 17and is provided with rollers 18 at its four corners for rolling movementin channel tracks 19 which extend horizontally along the interiorsurfaces of the sidewalls l0 and l l.

A series of paper feed rollers are mounted upon carriage l7 and includea pair of upper feed rollers 21 and 22 and a pair of lower feed rollers23 and 24 which lie directly beneath the upper feed rollers so that thecopy paper passes vertically downwardly between the two pairs ofrollers. Copy paper is inserted between a pair of spaced copy paperguide plates 27 and 28 which are mounted upon carriage 17 forlongitudinal movement therewith. A sheet of copy paper29 is showninserted between guide plates 27 and 28 for introduction to the uppersides of rollers 21 and 22. v

The apparatus and method illustrated and described herein by way ofexample is of the type known in the art ,as the Electrofax methodwherein the copy paper has a zinc oxide coating. However, the principlesof the present invention apply equally to Xerographic copying and infact to any copying method to which the principles inherent herein areadaptable.

From the rollers 21 and 22 the copy paper passes vertically downwardlyto the rollers 23 and '24. The roller 24 primarily controls the speed ofmovement of the paper and, as will be seen later herein, thesynchronized horizontal movement of carriage 17. To this end the roller24 is the primary paper feed roller and is driven at a very slightlyfaster rate than thecorresponding upper drive roller 22 to insure thatthe paper is taut in the vertical space between the upper and lower pairof rollers.

From the rollers 21 and 22 the copy paper 29 passes through a coronadischarge device 31 which sensitizes the paper by applying anelectrostatic charge thereto according to copying principles which arecommon to the Electrofax copying method. Between corona discharge device31 and lower rollers 23 and 24 is the zone in which an image of themanuscript, which is designated 30 in FIG. 1, is applied to the copypaper. A mirror 33 disposed at a 45 angle reflects an image of themanuscript 16 through lens means 34 and to the surface of copy paper 29.A lamp 35 also mounted upon carriage 17 illuminates the surface ofmanuscript 30.

After exposure of the sensitized surface of the copy paper in thismanner the same moves through a liquid developer or toner 37 containedin a tank 38 fixed to the underside of carriage l7 and then passesoutwardly between a pair of rollers 40 and 41 and onto a chute 42 fordelivery.

As shown in FIG. 2 and 3, a drive motor 45 and reducer unit 46 operate adrive pulley 47 which is connected to pulleys 48 and 49 which arecarried by rollers 24 and 40 by a toothed belt 50. A second outputpulley SI of the reducer 46 drives a pulley 52 fixed to upper driveroller 22 by means of a belt 53.

Reference will now be had to the means for moving carriage l7longitudinally in accurate synchronism with the rotation of paper feedroller 24. A pair of pulleys 55 and 56 are fixed to the shaft of paperfeed roller 24 for rotation jointly with roller 24 and traction cables57 and 58 are wrapped around pulleys 55 and 56, respectively.Corresponding ends of the cables 57 and 58 are fixed to the end of thestationary frame portion of the machine, as indicated at 59 and 60 inFIGS. 2 and 3, and the opposite ends of the two cables are attached to avertical spindle 61 mounted at the opposite end of the machine frame.The cables 57 and 58 are attached to spindle 61 in such manner thatclockwise rotation of spindle 61, as viewed from above, tightens cable58 by wrapping the same around the spindle and loosens cable 57, whereascounterclockwise rotation of spindle 61 tightens cable 57 and loosenscable 58. Pulley 55 and traction cable 57 effect forward operatinglongitudinal movements of carriage 17, that is, movements from left toright as viewed in FIGS. 1 and 3, whereas pulley 56 and cable 58 effectreturn movements.

Pulley 55 is of such size that its effective diameter with respect tocable 57 is substantially identical with the effective peripheral paperfeeding diameter of roller 24. Accordingly, when cable 57 is taut, asduring operating strokes of carriage l7, downward movements of copypaper 29 as controlled by rotation of paper feed roll 24 are exactlyduplicated by synchronized horizontal movements of carriage 17 which areproduced by pulley 55 in effect rolling along cable 57.

As will presently appear, such forward movements of carriage 17 occurwhen spindle 61 is in a counterclockwise'position of adjustment. Whenspindle 61 is in a clockwise position of adjustment, cable 57 isloosened and cable 58 is taut, and since the latter is wrappedoppositely on pulley 56 from the direction of wrapping of cable 57 orpulley 55, return movements of the carriage are effected. In the presentinstance, pulley 57 is greater in diameter than pulley 55 whereby morerapid return strokes are produced.

The energizing circuit for motor 45 includes a normally closedmicroswitch 64 which is mounted on the stationary framework of themachine and a cam plate 65 fixed to carriage 17 engages and opensmicroswitch 64 at the end of a return stroke of carriage 17. The partsare shown in this position of rest between operating cycles in FIGS. 1and 3.

A normally open microswitch 66 is fixed to the opposite end of themachine framework as shown in FIGS. 1, 3 and 4, and microswitch 66 isconnected in parallel with microswitch 64. Referring particularly toFIG. 4, to start a cycle of operation the operator rotates spindle 61 ina counterclockwise direction by means of a manipulating knob 67 whichbrings an operating pin 68, which is fixed to a block 69 carried byspindle 61, into engagement with an operating member 70 of microswitch66 to close the latter. This establishes an energizing circuit for motor45 in parallel with microswitch 64 and thus energizes the motor untiloperator 65 releases microswitch 64 which then closes until thecompletion of an operating and return cycle of movement.

When the operator thus initiates a cycle of operation bycounterclockwise rotation of spindle 61 a projection 75 of block 69latches into a notch 76 in an arm 77 which is biased in a clockwisedirection by an extension spring 78. This retains spindle 61 in itscounterclockwise limit of movement as illustrated in FIG. 3 and thismovement of spindle 61 also tightens cable 57 to produce synchronizedlongitudinal forward movement of carriage 17, that is, movement fromleft to right as viewed in FIGS. 1 and 3.

When a forward stroke approaches completion a projecting member 80carried by carriage 17 engages arm 77 to move the same in acounterclockwise direction and release the projection 75, whereuponspindle 61 automatically rotates in a clockwise direction under theimpetus of a biasing extension spring 81 which loosens cable 57 andtightens return cable 58 for a return stroke of movement of carriage 17.This movement of spindle 61 also permits microswitch 66 to open but theoperating circuit for motor 45 is maintained through normally closedmicroswitch 64 until the return stroke of movement of carriage 17 iscompleted, whereupon member 65 opens microswitch 64 as previouslydescribed.

The foregoing arrangement is such that the completed copy is ultimatelydelivered after the carriage has made a full copying and return strokeso that the copy is released from the final rollers 40 and 41 at thecarriage position illustrated in FIG.'1, and the copy at this pointactually protrudes from the lefthand end of the machine by an inch or sofor convenient grasping. It will be noted that at the time when reachesits extreme right-hand position, as viewed in FIG. 1, that is, at thecompletion of the scanning, the trailing endportion of the copy paper isstill engaged by the rollers 21, 22, 23 and 24 even though the leadingend of the copy paper has passed through tank 38 and is engaged byrollers 40 and 41.

During the ensuing return movement of the carriage from right to left,as viewed in FIG. 1, the copy paper completes its passage through tank38 and, as stated above, is released by passage of its trailing end fromrollers 40 and 41 at substantially the completion of the return movementof the carriage.

The principles of the present invention are equally applicable toelectrophotographic copying processes and apparatus wherein a dry toneris employed instead of the liquid toner previously described. Thechemical constituents of wet and dry toners employed in Electrofaxcopying processes are well known in this art. FIG. 6 shows a dry tonerarrangement which may be substituted for the wet toner tank 38 of theprevious embodiment. FIG. 6 is generally schematic and the paper feedrollers and the corona discharge element are designated by the samenumerals as in the previous embodiment. From the lower rollers 23 and 24the exposed copy paper passes to a table to the bottom of which a tankor reservoir for dry toner, designated 91, is attached.

Conventional dry toners usually incorporate iron filings orferromagnetic powder mixed with resin particles and a magnetic roller 92picks up this mixture of dry particles, designated 93, and brushes thesame against the exposed surface of copy paper 29. The paper is thensubjected to heat, as is conventional, by means of a heat-radiatingdevice 94 and a fan 95 may be provided for directing the heat againstthe surface of the copy paper.

A further improvement of the present invention involves the dry tonerper se. In conventional dry toners, as stated above, iron filings andresin particles are mixed and the resin toner particles, being higher inthe triboelectric series, acquire a positive charge and the ironparticles a negative charge. Dry toners present a problem in maintainingthorough admixture of the iron and resin particles and for maintainingthe proper balance or proportion between those particles.

The present invention contemplates a novel dry toner wherein theindividual ferromagnetic or iron particles are encapsulated with theresin material which comprises the toner per se. Thus the encapsulatediron particles serve their electromagnetic function through theencapsulating'plastic film and the plastic material is applied directlyto the electrostatic image on the exposed zinc oxide coated copy paper.In this way the problem of uniform admixture of iron and plasticparticles is completely eliminated and the proportions of theseparticles are absolutely constant. Furthermore, initial and directcontact of the toner with the surface of the copy paper is by theplastic film which is the active toning agent.

Obviously, many modifications and variations of the present inventionwill occur to those skilled in this art in the light of the teachings ofthe foregoing disclosure. It is therefore to be understood that, withinthe scope of the appended claims, the invention may be practicedotherwise than as specifically described above.

We claim:

1. In an electrophotographic copying machine, a stationary supporthaving a horizontal transparent plate adapted to receive manuscript tobe copied in facedown position thereon, a carriage mounted forhorizontal movement relative to said support beneath said transparentplate to effect linear panoramic scanning of said manuscript, saidcarriage having an image-receiving zone, roller means mounted on saidcarriage for feeding copy paper through said carriage past saidimage-receiving zone, optical means mounted on said carriage forreceiving a panoramic image from said manuscript and projecting the sameto said imagereceiving zone, means driven directly from said paper feedroller means for moving said carriage horizontally through forward andreturn strokes inaccurate synchronism with movements of said copy paperthe carriage to reproduce an image of said manuscript on said copy paperand return the carriage to initial position means mounted on saidcarriage adjacent to said image-receiving zone containingelectrophotographic toner material, and means for directing said copypaper emerging from said image-receiving zone directly into surfacecontact with said toner material and for delivering the same from themachine at the conclusion of the return stroke of said carriage.

2. A copying machine according to claim 1 wherein copy paper is fedvertically past said image-receiving zone and wherein said optical meansprojects said panoramic image horizontally to said vertically movingcopy paper at said image-receiving zone.

3. A copying machine according to claim 1 wherein said copy paperfeeding roller means is motor driven and wherein said carriage-movingmeans comprises a drive wheel fixed to said paper feed roller means forrotation therewith.

4. A copying machine according to claim 1 wherein said optical meanscomprises a mirror positioned to reflect said panoramic image towardsaid image-receiving zone.

5. in an electrophotographic copying machine, a support having ahorizontal transparent plate adapted to receive manuscript to be copiedin facedown position thereon, a carriage mounted for horizontal movementrelative to said support beneath said transparency to effect linearpanoramic scanning of said manuscript, roller means for feeding copypaper through said carriage past an image-receiving zone, optical meanson said carriage for receiving a panoramic image from said manuscriptand projecting the same to said imagereceiving zone, means driven fromsaid paper feed roller means for moving said carriage horizontally inaccurate synchronism with movements of said copy paper to reproduce animage of said manuscript on said copy paper, said feed roller comprisinga pulley, a traction cable having a portion thereof wrapped around saidpulley and its ends extending to opposite ends of said machine, andmeans for tightening said cable whereby rotation of said pulley causesthe pulley to rotate along said cable and thereby move said carriagehorizontally in accurate synchronism with said copy paper feed roller.

6. In an electrophotographic copying machine, a support having ahorizontal transparent plate adapted to receive manuscript to be copiedin facedown position thereon, a carriage mounted for horizontal movementrelative to said support beneath said transparency to effect linearpanoramic scanning of said manuscript, roller means for feeding copypaper'through said carriage past an image-receiving zone, optical meanson said carriage for receiving a panoramic image from said manuscriptand projecting the same to said imagereceiving zone, means driven fromsaid paper feed roller means for moving said carriage horizontally inaccurate synchronism with movements of said copy paper to reproduce animage of said manuscript on said copy paper, said roller means beingmotor driven and said carriage moving means comprising a drive wheelfixed to said paper feed roller means for rotation therewith, said drivewheel comprising a pulley, a traction cable having a portion thereofwrapped around said pulley and its ends extending to opposite ends ofsaid machine, and means for tightening said cable whereby rotation ofsaid pulley causes the pulley to rotate along said cable and therebymove said carriage horizontally in accurate synchronism with said copypaper feed roller.

7. A copying machine according to claim 6 wherein copy paper is fedvertically past said image-receiving zone and wherein said optical meansprojects said panoramic image horizontally to said vertically movingcopy paper at said image-receiving zone.

8. A copying machine according to claim 7 wherein copy paper is fedvertically past said image-receiving zone and wherein said optical meansprojects said panoramic image horizontally to said vertically movingcopy paper at said image-receiving zone.

1. In an electrophotographic copying machine, a stationary supporthaving a horizontal transparent plate adapted to receive manuscript tobe copied in facedown position thereon, a carriage mounted forhorizontal movement relative to said support beneath said transparentplate to effect linear panoramic scanning of said manuscript, saidcarriage having an image-receiving zone, roller means mounted on saidcarriage for feeding copy paper through said carriage past saidimage-receiving zone, optical means mounted on said carriage forreceiving a panoramic image from said manuscript and projecting the sameto said imagereceiving zone, means driven directly from said paper feedroller means for moving said carriage horizontally through forward andreturn strokes in accurate synchronism with movements of said copy paperto reproduce an image of said manuscript on said copy paper and returnthe carriage to initial position means mounted on said carriage adjacentto said image-receiving zone containing electrophotographic tonermaterial, and means for directing said copy paper emerging from saidimage-receiving zone directly into surface contact with said tonermaterial and for delivering the same from the machine at the conclusionof the return stroke of said carriage.
 2. A copying machine according toclaim 1 wherein copy paper is fed vertically past said image-receivingzone and wherein said optical means projects said panoramic imagehorizontally to said vertically moving copy paper at saidimage-receiving zone.
 3. A copying machine according to claim 1 whereinsaid copy paper feeding roller means is motor driven and wherein saidcarriage-moving means comprises a drive wheel fixed to said paper feedroller means for rotation therewith.
 4. A copying machine according toclaim 1 wherein said optical means comprises a mirror positioned toreflect said panoramic image toward said image-receiving zone.
 5. In anelectrophotographic copying machine, a support having a horizontaltransparent plate adapted to receive manuscript to be copied in facedownposition thereon, a carriage mounted for horizontal movement relative tosaid support beneath said transparency to effect linear panoramicscanning of said manuscript, roller means for feeding copy paper throughsaid carriage past an image-receiving zone, optical means on saidcarriage for receiving a panoramic image from said manuscript andprojecting the same to said image-receiving zone, means driven from saidpaper feed roller means for moving said carriage horizontally inaccurate synchronism with movements of said copy paper to reproduce animage of said manuscript on said copy paper, said feed roller comprisinga pulley, a traction cable having a portion thereof wrapped around saidpulley and its ends extending to opposite ends of said machine, andmeans for tightening said cable whereby rotation of said pulley causesthe pulley to rotate along said cable and thereby move said carriagehorizontally in accurate synchronism with said copy paper feed roller.6. In an electrophotographic copying machine, a support having ahorizontal transparent plate adapted to receive manuscript to be copiedin facedown position thereon, a carriage mounted for horizontal movementrelative to said support beneath said transparency to effect linearpanoramic scanning of said manuscript, roller means for feeding copypaper through said carriage past an image-receiving zone, optical meanson said carriage for receiving a panoramic image from said manuscriptand projecting the same to said image-receiving zone, means driven fromsaid paper feed roller means for moving said carriage horizontally inaccurate synchronism with movements of said copy paper to reproduce animage of said manuscript on said copy paper, said roller means beingmotor driven and said carriage moving means comprising a drive wheelfixed to said paper feed roller means for rotation therewith, said drivewheel comprising a pulley, a traction cable having a portion thereofwrapped around said pulley and its ends extending to opposite ends ofsaid machine, and means for tightening said cable whereby rotation ofsaid pulley causes the pulley to rotate along said cable and therebymove said carriage horizontally in accurate synchronism with said copypaper feed roller.
 7. A copying machine according to claim 6 whereincopy paper is fed vertically past said image-receiving zone and whereinsaid optical means projects said panoramic image horizontally to saidvertically moving copy paper at said image-receiving zone.
 8. A copyingmachine according to claim 7 wherein copy paper is fed vertically pastsaid image-receiving zone and wherein said optical means projects saidpanoramic image horizontally to said vertically moving copy paper atsaid image-receiving zone.